i'm 5'0" so half a pound on top of textbooks makes a Big differenceI might be belong to a niche category since I used to carry around a 17 inch 9.5 lbs (4.3 kg) laptop along with notebooks and other stuff back in my university day so I don't understand while people keep bitching about 4.5 lbs vs 4 lbs. And I wan't big either. At that time I was 5'9 at 121 lbs with a thin small frame.
To me anything under 6 lbs is portable enough for daily carry.